Charging of spinning insulating ob jects by plasma and photoemission

TL;DR

This study investigates how spinning insulating objects charged by plasma and photoemission exhibit dynamic charge redistribution, oscillations, and plasma interactions, using particle-in-cell simulations to reveal complex charging behaviors.

Contribution

It introduces a detailed simulation analysis of spinning insulating objects under plasma and photoemission, highlighting the effects of rotation and plasma conditions on charge dynamics.

Findings

Photoemission can induce positive charge and dipole moments.

Object spin causes surface charge redistribution and oscillations.

Plasma density and potential oscillate with object rotation period.

Abstract

The charging of spinning insulating objects by plasma and photoemission is studied with the particle-in-cell method. Unidirectional photon flux, different angular velocities of the object, and different plasma flow speeds are considered. Photoemission can lead to a positive total charge and electric dipole moment on the object. The spinning of the object redistributes the surface charge. The total object charge oscillates in time with the period matching the period of the object rotation. Plasma potential and density in the vicinity of the object oscillate with the same frequency. The plasma is rarefied close to a positively charged object, and the density wake diminishes when the object is charged negatively. The time averaged charge depends on the angular velocity of the object.